1. Field of the Invention
This invention relates to rock crushing machines having a conical head and a surrounding shell that defines therebetween an annular crushing chamber, and in particular to such a machine having a feed distributor for evenly discharging feed to the annular crushing chamber. More particularly, this invention is an improvement to the feed distributing arrangement disclosed in U.S. Pat. No. 3,785,578.
2. Description of the Prior Art
Crushers known to the prior art which include feed distributing devices are of various types.
One type involves transmitting the motion of a crushing cone, or the motion transmitted to a crushing cone, through gears or pulleys, to a feed distributor over the annular crushing chamber. By the selection of gear or pulley sizes and design of the gear train the feed distributor may be made to turn at a selected speed which may be faster or slower than the drive turns the cone or an eccentric bearing around the cone shaft. A feed distributor of this type is shown in U.S. Pat. No. 475,330. More modern versions of such a feed distributor are shown in, for example, U.S. Pat. Nos. 2,621,860 and 2,917,247.
Another type provides a feed distributing cone pan or plate resiliently mounted above the crushing chamber and flexibly connected to the crushing cone so the turning or gyrating motion of the crushing cone causes the feed distributor to wobble and this motion is utilized to distribute feed material around the annular crushing chamber. Such a feed distributor is shown in U.S. Pat. Nos. 1,761,240; 2,586,122 and 2,656,120.
Neither of the first two types of the prior art have any provision for adjusting the speed of operation of the feed distributor while the crusher was in operation and independent of the rate of gyration or rotation of the crushing head. Still another type has one or more drive motors separate and independent of the crusher drive. The feed distributor of this type can be adjusted to operate at selected rates independent of the rate of gyration or rotation of the crusher head. U.S. Pat. Nos. 2,737,289; 3,212,720; 3,358,939; 3,384,215 and 3,565,353 are illustrative of this type of crusher. In such machines force is applied to the feed material to move the feed in a generally horizontal plane to a location over the crushing chamber where gravity is relied upon to direct the material between the cone and the surrounding shell structure.
A further type is exemplified in U.S. Pat. Nos. 3,506,203 and 3,604,636, which disclose feed distributors that direct a flow of feed material around an annular crushing chamber and down an inclined path.
Still another type of material distributor is of the rock and roll type and is connected to move with the crusher head thereby taking part of the gyratory movement of the crusher head. This type of distributor has the disadvantage of being dependent at the rate at which the material is fed to the distributor. Variations in the feed causes a variation in the manner in which the material is distributed to the crushing chamber, the material sometimes being heavy and sometimes light. U.S. Pat. Nos. 2,207,858; 2,656,120 and 3,614,023 are of this type.